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What do you see when you look at an
aerial photograph?
If you haven't looked at an aerial photograph, you might
be surprised what you can and can't see. You can easily see
roads, geographic features such as shores, mountains, the
larger rivers, lakes, landslides, faultlines, etc. Creeks
and smaller rivers can be obscured by the trees that often
grow along them. Depending on the scale, you may be able to
see parks, individual buildings, and similar-sized objects
in the landscape. A serials of aerials of the same area can
show you urban growth or the loss/increase in farming or changes
in the road structure. What you usually can't see with aerials
are small landscape features such as details on fences, yards,
buildings, or a property's berms. In addition, your area of
interest may not have been in the path of any of the flights
we have.
See Geographic
Index pages for information on the flights we own and
the areas they cover.
See our examples of the
different formats and scales you can see in our aerials.
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Aerial Photograph Formats
Aerials also come in three basic types: black & white,
color, and color-infrared. Black & white shows good contrast
and detail. We have B&W photos dating back to 1928. Beginners
often like the color photos, because it is sometimes easier
for them to identify familiar objects using the color. Our
earliest color photos are from 1973. Color-infrared can show
landscape features that otherwise aren't very clear, but they
present these features in "false" (that is, unfamiliar)
colors.
What is scale?
Scale on an aerial photograph is the ratio
between the size of the object in the photo compared to the
size of the object that was photographed. We indicate these
by notation: 1:4200, 1:7200, 1:28,000, and so on. The smaller
the number after the colon, the closer to the ground the picture
was taken. These can be roughly translated into feet and inches.
For instance, 1:4200 means that 1 inch on the photograph equals
350 feet on the ground (350 X 12 = 4200); 1:7200 means that
1 inch on the photograph equals 600 feet on the ground (600
X 12).
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